<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        /* 
            我们js这门编程语言从设计到发布的第一个版本
                10天左右
                所以,JS里面存在着很多的bug
        */
        // var var = 10;
        // var alert = 20;
        // console.log(alert);

        // var break = 10;
        // var for = 20;
        // var if = 30;

        var userName = "张三"
        var userPassword = "123456"
    </script>
</body>
</html>